(CNN) -- Teams in their sixth day of searching for a missing plane in Wyoming were attempting to stay ahead of bad weather Sunday. Two search teams spent Saturday night at an elevation of 10,000 feet because of "blizzard-like" conditions, authorities said.

The plane had four people on board, members of a Minnesota family, according to the Fremont County, Wyoming, Sheriff's Office. It took off from the Jackson Hole, Wyoming, airport on Monday. It was bound for Riverton, Wyoming, en route to Minneapolis-St. Paul, Minnesota.

"As day six of active searching begins, no physical evidence of the missing aircraft has been found," the sheriff's office said in a statement Sunday. "At the incident command center Sunday morning ... fresh snow was visible on the peaks of the Wind River Range."

Searchers have been working in a very remote area at elevations of up to 13,000 feet, the sheriff's office has said.

A Wyoming National Army Guard Blackhawk helicopter was able to remove one ground team, which reported it was nearly "socked in" with "blizzard-like conditions" at the landing zone, authorities said. However, two other teams were forced to spend the night in the area.

"We tried to extract the teams by helicopter, but the weather closed in and they had to spend the night," said Jason Aanestad, incident command operations chief, in the sheriff's office statement. Authorities planned Sunday morning to put in a fresh ground team and remove the other two, he said.

The weather cleared Saturday night, the sheriff's office said, and searchers Sunday had mostly cloudy skies and temperatures in the high 20s. "The weather, however, is expected to close in again late Sunday afternoon," authorities said.

The search plan for Sunday includes using a helicopter in a grid search as well as ground teams, the statement said.

Searchers received a boost on Saturday when they received messages of prayers and support from friends and colleagues of the missing family. After receiving a pile of hand-written notes, the sheriff's office said, searcher Andy Basset -- who had just been plucked from the blizzard -- said, "I wish we could go out again right now."

Snow, high winds and low visibility have hampered the search since it began. The sheriff's office has not identified the identities of those thought to be on board the plane and has also not said whether children were on board.

However, the Minneapolis Star Tribune reported that the plane carried Luke Bucklin, 40, and his three sons -- 14-year-old twins Nate and Nick, and 12-year-old Noah. A prayer gathering was held for the family Friday night, the newspaper reported.